Demographic Characteristics, Clinical Features, and Treatment Patterns of Classic and AIDS-Related Kaposi Sarcoma: A Multicenter Real-World Study from Turkey

Background and Objectives: Kaposi sarcoma (KS) is a rare angioproliferative malignancy driven by human herpesvirus-8 infection. Comparative real-world data on classic and AIDS-related KS from Mediterranean-endemic countries remain limited. Materials and Methods: We retrospectively analyzed 102 patients with histopathologically confirmed KS treated across five tertiary oncology centers in Turkey between January 2010 and December 2023. Demographic characteristics, clinical features, treatment patterns, and survival outcomes were compared between classic and AIDS-related KS subtypes. Results: Ninety-two patients (90.2%) had classic KS and ten (9.8%) had AIDS-related KS. The median age at diagnosis was significantly higher in the classic KS group (69 vs. 38.5 years; p < 0.001). Male sex predominated in both groups (classic KS: 76.1%; AIDS-related KS: 100%; p = 0.113). AIDS-related KS presented with more advanced disease at diagnosis, with 70% classified as poor-risk by ACTG-TIS criteria versus 9.8% Stage IV by Brambilla criteria in classic KS, and more frequent extracutaneous involvement (70% vs. 8.7%; p < 0.001). Paclitaxel was the most commonly used first-line agent in classic KS (42.9%), while pegylated liposomal doxorubicin predominated in AIDS-related KS (87.5%). Overall response rates were high and comparable between groups (90.7% vs. 88.9%). Median overall survival was significantly longer in classic KS (66.9 vs. 22.67 months; p = 0.012). Disease stage and lesion morphology were not significantly associated with survival in either group. Conclusions: Classic and AIDS-related KS differ substantially in clinical presentation and survival outcomes, yet demonstrate comparable chemosensitivity. Our findings in the AIDS-related Kaposi sarcoma group are preliminary and hypothesis-generating due to the small sample size, requiring confirmation in larger prospective cohorts.